Regarding non-contact power supply of supplying power from a power supply apparatus to a power receiving apparatus in a non-contact manner, for example, Patent Literature 1 describes a wireless charging system including a wireless charging apparatus including a power transmission device that transmits power for charging, a power receiving apparatus that includes a power receiving device which receives the power transmitted from the wireless charging apparatus by a magnetic resonance relation and that charges the received power to a battery, and a relay device capable of relaying the transmission power of the power transmission device of the wireless charging apparatus.
Patent Literature 2 describes that, in a wireless system including a sheet-like body, a power transmission side resonance coil that is supplied with power and transmits the power, and at least one relay coil capable of receiving and transmitting the transmitted power by a magnetic resonance relation, the power transmission side resonance coil and the relay coil are formed in a sheet shape, and the power transmission side resonance coil and the relay coil are arranged on the sheet-like body at a predetermined interval.
Patent Literature 3 describes that, in a wireless power supply system including a power transmission device including a first resonance element that is supplied with power and transmits the power, a relay device including a second resonance element that receives and transmits the transmitted power by a magnetic resonance relation, and a power receiving device including a third resonance element that receives the power transmitted from the relay device by the magnetic resonance relation, the relay device adjusts at least one of an arrangement angle and an arrangement position of the second resonance element according to power transmission information of at least one of the power transmission device and the power receiving device.